# Time Topics

Adafruit IO provides some built-in MQTT topics for getting the current server time. The current available topics are:

* `time/seconds`
* `time/millis`
* `time/ISO-8601`
* `time/hours`

Most of the Adafruit IO client libraries provide helper functions for easy use of these topics:

* [Arduino](https://github.com/adafruit/Adafruit_IO_Arduino/blob/master/examples/adafruitio_17_time_subscribe/adafruitio_17_time_subscribe.ino)
* [Python](https://github.com/adafruit/Adafruit_IO_Python/blob/master/examples/mqtt/mqtt_time.py)
* [CircuitPython](https://github.com/adafruit/Adafruit_CircuitPython_AdafruitIO/blob/master/examples/adafruit_io_mqtt/adafruit_io_time.py)

## time/seconds

This topic publishes the current time in [Unix epoch seconds](https://en.wikipedia.org/wiki/Unix_time).

The current Unix epoch time at the time of writing is: `1562164754`.


## time/millis

This topic publishes the same thing as time/seconds every second, but with slightly higher precision and more digits.

The current Unix epoch time in milliseconds at the time of writing is: `1562165081839`


## time/ISO-8601

This topic publishes the current time in [ISO 8601 UTC format](https://en.wikipedia.org/wiki/ISO_8601). That's `year-month-dayThour:minute:second.millisecondsZ` where "-", ":", "T", and "Z" are character literals / always included in the time string.

The current time in ISO 8601 UTC format at the time of writing is: `2019-07-03T14:47:16.038Z`


## time/hours

This topic publishes the current hour of the day in 24 hour format (the values 0 - 23) in the UTC time zone. It only publishes once every hour.
